Referring to FIG. 1, a notebook computer 11 of the prior art has a plurality of key 112 on a keyboard main body 111. Since the arrangement of the keys 112 associated with a notebook computer 11 has to be compact, the density and the size of the keys 112 are high and small, which contribute to the typing errors committed by a user. On the other hand, a user has to be cautious during a typing process so as to illuminate typos. Therefore, a user will become tired of using a notebook computer 11 after a period of time. And therefore, there will be beneficial that an effect of visual appeal is added to a notebook computer, so that a user will be more motivated to use the computer.